Inkjet printers employ printheads for ejecting ink through nozzles of fluid drop generators onto a print media. For various reasons, the fluid ejectors or nozzles can fail to operate properly, which can adversely affect print quality. Nozzle health tests can be done to detect nozzles which are not operating normally. It is known to use isolated drop detection systems with optical detectors to detect nozzle health during special test modes. These systems are expensive and use up ink and time for the testing.